www.fairchildsemi.com KA3511DS Intelligent Voltage Mode PWM IC Features Description • • • • • • • • • • • • • • The KA3511DS is a fixed frequency improved performance pulse width modulation control circuit with complete housekeeping circuitry for use in the secondary side of SMPS (Switched mode power supply). It contains various functions, which are precision voltage reference, over voltage protection, under voltage protection, remote on/off control, power good signal generator and etc. Complete PWM control and house keeping circuitry Few external components Precision voltage reference trimmed to 2% Dual output for push-pull operation Each output TR for 200mA sink current Variable duty cycle by dead time control Soft start capability by using dead time control Double pulse suppression logic Over voltage protection for 3.3V / 5V / 12V Under voltage protection for 3.3V / 5V / 12V One more external input for various protection (PT) Remote on/off control function (PS-ON) Latch function controlled by remote and protection input Power good signal generator with hysteresis OVP (Over voltage protection) section It has OVP functions for +3.3V,+5V,+12V and PT outputs. The circuit is made up of a comparator with four detecting inputs and without hysteresis voltage. Especially, PT (Pin18) is prepared for an extra OVP input or another protection signal. UVP (Under voltage protection) section Precision reference section The reference voltage trimmed to ± 2% (4.9V ≤ Vref ≤ 5.1V) PG (Power good signal generator) section Power good signal generator is to monitor the voltage level of power supply for safe operation of a microprocessor. KA3511DS requires few external components to accomplish a complete housekeeping circuits for SMPS. It also has UVP functions for +3.3V, +5V, +12V outputs. The block is made up of a comparator with three detecting inputs and without hysteresis voltage. Remote on/off section Remote on/off section is used to control SMPS externally. If a high signal is supplied to the remote on/off input, PWM signal becomes a high state and all secondary outputs are grounded. The remote on/off signal is transferred with some on-delay and off-delay time of 8ms, 24ms respectively. 24-SDIP 1 Rev. 1.0.0 ©2001 Fairchild Semiconductor Corporation KA3511DS Internal Block Diagram RT 7 CT COMP OSCILLATOR PWM CONTROL 8 3 E/A(+) 4 CK Q Delay Controller R DEAD TIME CONTROLER 24 C1 22 C2 Q 23 E 5 TREM 6 S 1.25V DEAD TIME CONTROL 21 REM (PS-ON) 1.4V 0.1V 14 Vref OVP COMP INTERNAL BIAS Vref Ichag Start Up Vcc Q 2 E/A(-) VREF D V5 PG 18 17 PT V12 16 V5 15 V3.3 Vref PG GENERATOR 1 11 V5 1.25V COMP3 1.8V!"0.6V DET 1.8V!"0.6V 9 COMP2 UVP COMP 10 19 20 TPG TUVP GND 1.25V ADSolute Maximum Ratings Parameter Symbol Value Unit VCC 40 V Collector output voltage VC1, VC2 40 V Collector output current IC1, IC2 200 mA Supply voltage PD 1.5 W Operating temperature TOPR −25 to 85 °C Storage temperature TSTG −65 to 150 °C Power dissipation(KA3511DS) Temperature Characteristics 2 Parameter Symbol Min. Typ. Max. Unit Temperature coefficient of Vref (-25°C≤Ta≤85°C) ∆Vref/∆T - 0.01 - %/°C KA3511DS Pin Definition : KA3511DS C1 E C2 DTC GND TUVP PT V12 V5 V3.3 Vref NC #24 #13 AS DS KA3511D #12 #1 Vcc COMP Pin Number Pin Name I/O 1 VCC I 2 COMP 3 E/A(-) EA(+) TREM REM RT CT DET TPG PG NC Pin Number Pin Name I/O Supply voltage 13 NC - NC O E/A output 14 Vref O Precision reference VTG E/A(-) I E/A (-) input 15 V3.3 I OVP, UVP input for 3.3V 4 E/A(+) I E/A (+) input 16 V5 I OVP, UVP input for 5V 5 TREM - Remote on/off delay 17 V12 I OVP, UVP input for 12V 6 REM I Remote on/off input 18 PT I Extra protection input 7 RT - Oscillation freq. setting R 19 TUVP - UVP delay 8 CT - Oscillation freq. setting C 20 GND - Signal ground 9 DET I Detect input 21 DTC I Deadtime control input 10 TPG - PG delay 22 C2 O Output 2 11 PG O Power good signal output 23 E - Power ground 12 NC - NC 24 C1 O Output 1 Pin Function Pin Function Descrition 3 KA3511DS Pin Number Pin Name 4 Pin Function Descrition 1 VCC 2 COMP Error amplifier output. It is connected to non-inverting input of pulse width modulator comparator. 3 E/A(-) Error amplifier inverting input. Its reference voltage is always 1.25V. 4 E/A(+) Error amplifier non-inverting input feedback voltage.This pin may be used to sense power supply output voltage. 5 TREM Remote on/off delay. Ton/Toff=8ms/24ms (Typ.) with C=0.1uF. Its high/low threshold voltage is 1.8V/0.6V. 6 REM Remote on/off input. It is TTL operation and its threshold voltage is 1.4V. Voltage at this pin can reach normal 4.6V, with aDSolutely maximum voltage, 5.25V. If REM = “Low”, PWM = “Low”. That means the main SMPS is operational. When REM = “High”, then PWM = “High” and the main SMPS is turned-off. 7 RT Oscillation frequency setting R. (Test Condition RT=10kΩ) 8 CT Oscillation frequency setting C. (Test Condition CT=0.01uF) 9 DET Under voltage detection pin. Its threshold voltage is 1.25V Typ. 10 TPG PG delay. Td=250ms (Typ) with CPG=2.2uF. The high/low threshold voltage are 1.8V/ 0.6V and the voltage of Pin10 is clamped at 2.9V for noise margin. 11 PG Power good output signal. PG = “High” means that the power is “Good” for operation and PG = “Low” means “Power fail”. 14 Vref Precision voltage reference trimmed to 2%. (Typical Value = 5.03V) 15 V3.3 OVP, UVP input for output 3.3V. (Typical Value = 4.1V/2.3V) 16 V5 OVP, UVP input for output 5V. (Typical Value = 6.4V/4.0V) 17 V12 OVP, UVP input for output 12V. (Typical Value = 14.2V/10V) 18 PT This is prepared for an extra OVP input or another protection signal. (Typical Value = 1.25V) 19 TUVP Timing pin for under voltage protection blank-out time. Its threshold voltage is 1.8V and clamped at 2.9V after full charging. Target of delay time is 250ms and it is realized through external (C=2.2uF). 20 GND Signal ground. 21 DTC Deadtime control input. The dead-time control comparator has an effective 120mV input offset which limits the minimum output dead time. Dead time may be imposed on the output by setting the dead time control input to a fixed voltage, ranging between 0V to 3.3V. 22 C2 23 E 24 C1 Supply voltage. Operating range is 10V~30V. VCC=20V, Ta=25°C at test. Output drive pin for push-pull operation. Power ground. Output drive pin for push-pull operation. KA3511DS Electrical Characteristics (Vcc=20V, Ta=25°°C) Parameter Symbol Condition Min. Typ. Max. Unit 4.9 5 5.1 V REFERENCE SECTION Reference output voltage Vref Line regulation Load regulation Temperature coefficient of Vref (1) Short-circuit output current Iref=1mA ∆Vref.LINE 10V ≤ VCC ≤ 30V - 2.0 25 mV ∆Vref.LOAD 1mA ≤ Iref ≤ 10mA - 1.0 15 mV ∆Vref/∆T -25°C ≤ Ta ≤ 85°C - 0.01 - %/°C 15 35 75 mA ISC Vref=0 fosc CT=0.01uF, RT=12k - 10 - kHz fosc/T CT=0.01uF, RT=12k - 2 - % OSCILLATOR SECTION Oscillation frequency Frequency change with temperature (1) DEAD TIME CONTROL SECTION Input bias current IB(DT) Maximum duty voltage DCMAX Input threshold voltage VTH(DT) - -2.0 -10 uA Pin19 (DTC)=0V - 45 48 50 % Zero Duty Cycle - 3.0 3.3 Max. Duty Cycle 0 - - 1.20 1.25 1.30 V - -0.1 -1.0 uA 70 95 - dB - 650 - kHz V ERROR AMP SECTION Inverting reference voltage Input bias current IB(EA) Open-loop voltage gain (1) Unit-gain bandwidth Vref(EA) (1) GVO BW VCOMP=2.5V 0.5V≤VCOMP≤3.5V - ISINK VCOMP=0.7V 0.3 0.9 - mA ISOURCE VCOMP=3.5V -2.0 -4.0 - mA VTH(PWM) Zero Duty Cycle - 4 4.5 V Output saturation voltage VCE(SAT) IC=200mA - 1.1 1.3 V Collector off-state current Output sink current Output source current PWM COMPARATOR SECTION Input threshold voltage OUTPUT SECTION IC(off) VCC=VC=30V, VE=0V - 2 100 uA Rising time TR - - 100 200 ns Falling time TF - - 50 200 ns 5 KA3511DS Electrical Characteristics (Continued) Parameter Symbol Condition Min. Typ. Max. Unit Over voltage protection for 3.3V VOVP1 - 3.8 4.1 4.3 V Over voltage protection for 5V VOVP2 - 6.0 6.4 6.8 V Over voltage protection for 12V VOVP3 - 13.5 14.2 15.0 V VPT - 1.20 1.25 1.30 V Under voltage protection for 3.3V VUVP1 - 2.1 2.3 2.5 V Under voltage protection for 5V VUVP2 - 3.7 4.0 4.3 V Under voltage protection for 12V VUVP3 - 9.2 10 10.8 V Charging current for UVP delay ICHG.UVP C=2.2uF, VTH=1.8V −10 −15 −23 uA TD.UVP C=2.2uF 100 260 500 ms REM on input voltage VREMH IREM=−200uA 2.0 - - V REM off input voltage VREML - - 0.8 V REM off input bias voltage IREML - - −1.6 mA 2.0 - 5.25 V PROTECTION SECTION Input threshold voltage for PT UVP Delay Time REMOTE ON/OFF SECTION REM on open voltage VREM=0.4V VREM(OPEN) - REM on delay time Ton C=0.1uF 4 8 14 ms REM off delay time Toff C=0.1uF 16 24 34 ms REMOTE ON/OFF SECTION (2) Detecting input voltage VIN(DET) - 1.20 1.25 1.30 V Detecting V5 voltage V5(DET) - 4.1 4.3 4.5 V Hysteresis voltage 1 HY1 COMP1, 2 10 40 80 mV Hysteresis voltage 2 HY2 COMP3 0.6 1.2 - V PG output load resistor RPG 0.5 1 2 kΩ C=2.2uF, VTH=1.8V −10 −15 −23 uA C=2.2uF 100 260 500 ms IPG=10mA - 0.2 0.4 V - - 10 20 mA Charging current for PG delay PG delay time PG output saturation voltage ICHG.PG TD.PG VSAT(PG) - TOTAL DEVICE Stanby supply current ICC Note: 1. These Parameters, although guaranteed over their recommended operating conditions are not 100% tested in production. 2. REM on delay time (Pin6 REM: “L” → “H”), REM off delay time (Pin6 REM: “H” → “L”) 6 KA3511DS Application Informations 300K VCC=15V IO - OSCILLATOR FREQUENCY 100K 0.001µF 10K CT=0.01µF 1K 0.1µF 1.0µF 100 30 1K 2K 5K 10K 20K 50K 100K 200K 500K 1M RT. TIMING RESISTANCE(Ω) Figure 1. Oscillator Frequency vs. Timing Resistance Ct Feedback Dead-time control Ck Q Q Output Q1 Output Q2 Figure 2. Operating Waveform 7 KA3511DS Housekeeping Circuit 2kΩ(1W ) 2kΩ(1W ) Standby Supply VCC=20V 1 VCC 2 COMP E 23 3 E/A(-) C2 22 4 E/A(+) DTC 21 GND 20 TUVP 19 C1 24 15kΩ 12V 5V 0.01u F 11kΩ 33kΩ 1.8k Ω 0.1uF 5 TREM 6 REM + 1kΩ Micom 7 RT K A 3 5 1 1 A D + 2.2uF PT 18 V12 17 12V 16 5V 15 3V S 12kΩ 8 + CT 0.01u F 2.2uF 9 DET V5 10 TPG V3.3 11 PG Vref + PG 14 1uF 12 13 Note : The KA3511DS requires few external components to accomplish a complete housekeeping circuits for SMPS. 8 + KA3511DS Typical Characteristics 0.014 5.010 0.012 5.008 Vref [V] ICC [A] 0.010 0.008 0.006 0.004 5.006 5.004 0.002 5.002 0.000 0 10 20 30 -40 40 -20 0 20 40 Supply Voltage [V] 80 100 120 140 TEMP [°C] Figure 3. VCC-ICC Figure 4. Bandgap Reference Voltage 50 5 40 4 31.1% 3 30 VPG [V] Duty Ratio [%] 60 21.8% 20 2 12.8% 10 1 0 0 0.0 0.5 1.0 1.5 2.0 3.6 2.5 2.73 3.0 3.8 4.0 Deadtime Control Voltage [V] 4.2 4.4 4.6 V3.3 [V] Figure 5. PIN19(Dead Time Control Voltage)-Duty Cycle Figure 6. OVP for 3.3V 7 5 5 4 4 3 VPG [V] VPG [V] 6 3 2 2 1 1 0 0 5.0 5.5 6.0 V5 [V] Figure 7. OVP for 5V 6.5 7.0 14.0 14.2 14.4 14.6 14.8 15.0 V12 [V] Figure 8. OVP for 12V 9 KA3511DS 5 5 4 4 3 3 VPG [V] VPG [V] Typical Characteristics (Continued) 2 2 1 1 0 0 1.15 1.20 1.25 1.30 21 1.35 23 24 25 Pin 13 (V3.3) Voltage [V] Vpt [V] Figure 10. UVP for 3.3V Figure 9. OVP for PT 5 5 4 4 VPG [V] VPG [V] 22 3 2 1 3 2 1 0 0 3.6 3.8 4.0 4.2 4.4 4.6 4.8 9.0 5.0 9.5 10.0 10.5 11.0 Pin 15 (V12) Voltage [V] Pin 14 (V5) Voltage [V] Figure 12 . UVP for 12V Figure 11 . UVP for 5V -0.000016 5 4 VPG [V] Irem [A] -0.000018 -0.000020 -0.000022 3 2 1 -0.000024 0 0 50 100 150 200 250 0 1 2 3 4 Vrem [V] Figure 13 . Remote ON Charging Current 10 Figure 14 . REM ON/OFF Vth 5 KA3511DS 5 5 4 4 VPG [V] Vrem [V] Typical Characteristics (Continued) 3 3 2 2 1 1 0 0 0 1 2 3 4 5 1.0 1.1 1.2 1.3 1.4 1.5 Pin 9 (DET) Voltage [V] Figure 15. Remote ON Open Voltage Figure 16. Detecting VCC Voltage (DET) -0.000005 5 -0.000010 IPG [V] VPG [V] 4 3 2 1 -0.000015 -0.000020 0 4.0 4.2 4.4 4.6 4.8 5.0 0 20 40 60 80 100 120 140 160 Pin 14 (5V) Voltage [V] Figure 18. Charging Current for PG Figure 17. Detecting V5 Voltage 5 -0.032 -0.033 VPG [V] Iref [A] 4 -0.034 3 2 1 -0.035 0 0 100 200 300 400 0.0 0.5 1.0 1.5 2.0 2.5 Pin 10 (TPG) Voltage [V] Figure 19. Short Circuit Current Figure 20. Hysteresis Voltage 2 11 KA3511DS Typical Characteristics (Continued) 0.002 5 4 -0.002 Vref [V] Isink & Isource [A] 0.00 -0.004 -0.006 3 2 1 -0.008 0 0 20 40 60 80 100 120 140 0 10 20 30 Supply Voltage [V] Figure 21. Error Amp Sink Current 12 Figure 22. Reference Voltage 40 KA3511DS Experimental Result CH1 : PS-ON CH2 : +5Vdc Output CH3 : PG Signal Figure 23. Rising Time of +5Vdc Output Voltage CH1 : PS-ON CH2 : +5Vdc Output CH3 : PG Signal Figure 24. PG Signal Delay Time 13 KA3511DS CH1 : PS-ON CH2 : +5Vdc Output CH3 : PG Signal Figure 25. Power Down Warning CH1 : +3.3Vdc Output CH2 : +5Vdc Output CH3 : +12Vdc Output Figure 26. No Load Protection 14 KA3511DS CH1 : Vcc CH2 : +5Vdc Output CH3 : PG Signal Figure 27. Vcc, +5Vdc Output vs. PG Signal (High) CH1 : Vcc CH2 : +5Vdc Output CH3 : PG Signal Figure 28. Vcc, +5Vdc Output vs. PG Signal (Low) 15 KA3511DS Application Circuit 47K 70K R6 R5 VCC 3 15K 4 POWER ON 5 + 0.1uF 6 OUT REF 7 8 103 9 10 + PG 2.2uF COMP E/A(-) C1 E C2 E/A(+) DTC TREM GND REM TUVP RT PT CT V12 DET TPG 11 V5 V3.3 PG NC 12 NC Vref NC NC BS AR3511X KA3511DS C1 24 22 23 21 22 20 R4 1.2K C2 19 21 20 18 17 19 18 16 R3 56K + 2 Vcc 2.2uF 17 15 5V OUT 15 13 3.3V OUT 14 12 13 D9 C16 VR1 + 16 C6 22uF 12V OUT 16 14 D19 100K + IC1 1 103 CT KA3511DS Mechanical Dimensions Package Dimensions in millimeters 24-SDIP 17 KA3511DS Ordering Information Product Number Package Operating Temperature KA3511DS 24-SDIP -25°C ~ 85°C DISCLAIMER FAIRCHILD SEMICONDUCTOR RESERVES THE RIGHT TO MAKE CHANGES WITHOUT FURTHER NOTICE TO ANY PRODUCTS HEREIN TO IMPROVE RELIABILITY, FUNCTION OR DESIGN. FAIRCHILD DOES NOT ASSUME ANY LIABILITY ARISING OUT OF THE APPLICATION OR USE OF ANY PRODUCT OR CIRCUIT DESCRIBED HEREIN; NEITHER DOES IT CONVEY ANY LICENSE UNDER ITS PATENT RIGHTS, NOR THE RIGHTS OF OTHERS. LIFE SUPPORT POLICY FAIRCHILD’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT OF FAIRCHILD SEMICONDUCTOR CORPORATION. As used herein: 1. Life support devices or systems are devices or systems which, (a) are intended for surgical implant into the body, or (b) support or sustain life, and (c) whose failure to perform when properly used in accordance with instructions for use provided in the labeling, can be reasonably expected to result in a significant injury of the user. 2. A critical component in any component of a life support device or system whose failure to perform can be reasonably expected to cause the failure of the life support device or system, or to affect its safety or effectiveness. www.fairchildsemi.com 11/9/01 0.0m 001 Stock#DSxxxxxxxx 2001 Fairchild Semiconductor Corporation